How to make list of gallery pages?

@mera.inventio, If I understand correctly, you want a page that automatically generates a list of available galleries in you site.

If so, a possible solution could be to add taxonomy tags to your gallery pages and create a collection based on these tagged pages. Then loop through the collection and create a list of anchors.

When you create a new gallery page or update an existing, the generated list will automatically be updated.

The following outlines the steps needed:

• Create an inherited theme based on theme 'Photographer' you are using. See Theme Inheritance steps 1-5
• Add a taxonomy to the pages that contain a gallery, like:
  YAMLCopy

  ---
  title: Cambio de Madrinas 2014
  taxonomy:
  category: gallery
  ---
  

  For docs on collections see https://learn.getgrav.org/16/content/collections

• Create a page 'galleries.md' that will contain links to all galleries. Add a collection definition to its header:
  YAMLCopy

  ---
  title: Listado de galerías
  content:
  items:
     '@taxonomy.category': gallery
  ---
  

  For docs on creating a collection on taxonomies see https://learn.getgrav.org/16/content/collections#taxonomy-collections

• Create a new template in your inherited theme named '/themes/mytheme/templates/galleries.html.twig' and loop through the collection of galleries to create a list of anchors. E.g.:

  TWIGCopy

  {% extends 'partials/base.html.twig' %}
  
  {% block content %}
   {% for gallery in page.collection() %}
       <a href="{{ gallery.url }}"><h3>{{ gallery.title }}</h3></a>
   {% endfor %
  {% endblock %}
  

Of course, you will need to add some extra html elements to create a suitable layout.

Hope this gives you an idea to play with...